Screw driver



June 20, 1944. PRALL 2,351,705

SCREW DRIVER Filed Dec. 9, 1942 IN 'TOR. usrm ALL Patented June 20, 1944 UNITED STATES PATENT OFFICE SCREW DRIVER Gustav Prall, New York, N. Y.

Application December 9, 1942, SerialNo. 468,338

1 Claim. (01. 14561) This invention relates to screw drivers and refers more particularly to handles thereof.

An object of the present invention is the provision of a screw driver having a revolving portion which is connected with a stationary portion in a firm, secure and effective manner..

Another object is the provision of a screw driver handle which may be conveniently made of any suitable composition material and which includes a portion receiving the pressure of the hand while the remaining portion of the screw driver rotates for the purpose of removing or inserting a screw.

Other objects of the present invention will become apparent in the course of the following specification.

In accomplishing the objects of the present invention, it was found desirable to provide a screw driver having a handle consisting of two main portions. One ofthese portions is firmly connected with a blade of the screw driver. The other portion rotates in relation to the first mentioned portion and is connected therewith by a stationary rivet, screw, or similar member. A hearing which may consist of a plate, a roller or the like is interposed between the two parts of the handle to facilitate rotation and diminish friction between the two parts.

The invention will appear more clearly from the following detailed description when taken in connection with the accompanying drawing, showing, by way of example, preferred embodiments of the inventive idea. a

In the drawing:

Figure 1 shows a screw driver in side elevation.

Figure 2 is a section along the line 2-2 on an enlarged scale.

Figure 3 is a top view of the screw driver shown in Fig. 1.

Figure 4 shows a somewhat differently constructed screw driver in side elevation.

Figure 5 is a section along the line 5-5 on an enlarged scale.

Figure 6 is a side view illustrating the rotary handle portion of the screw driver shown in Fig-4.

Figure 7 is a top view of the stationary part of the handle of the screw driver shown in Fig. 4.

The screw driver shown in Figures 1, 2 and 3 of the drawing, includes a blade 8, having an operative lower end 9, and an upper end In, which is firmly embedded in th stationary handle portion H. The handle portion may be cylindrical in form and may include one or more annular grooved portion l2, as well as transverse ribs for facilitating the grasping of the handle.

The top portion 13 of the handle is rotatable in relation to the portion II. The portion 13 is mounted upon a pivot or rivet M, which is inserted with a pressed fit into the handle portion II and is firmly embedded therein. Preferably the pivot l l is located in the center of the handle portion II and at the top thereof. The conical head I5 of the pivot I4 is located within a recess 5 formed in the handle portion 13. The portion l3 may be separated from the portion II by a groove or recess H.

The recess I6 is covered by a plate I 8 which is firmly embedded in the handle portion l3 and is rotatable therewith. Due to this arrangement the finger of the hand of the user does not come in contact with the pivot l 4.

A plate I9 is interposed between the handle portions II and I3. The plate l9 has an opening through which the pivot I4 extends, and it is made of any suitable material which will diminish friction between a rotary and a stationary surface.

In operation, the user engages a screw with the end 9 of the screw driver and at the same time presses against the handle portion l3, this pressure extending in the longitudinal direction of the screw driver. With the other hand the user turns the handle portion I l and the blade 8 connected therewith. The pivot M will rotate along with the handle portion II but the plate I8, and the handle portion I3 will remain stationary serving as a convenient support for the hand, the pressure of which is transmitted to the blade 8.

It is apparent that the described screw driver head is inexpensive to manufacture and may be conveniently fitted to any existing screw driver. The handling and the manipulation of a screw driver are greatly facilitated by the described construction.

The screw driver shown in Figures 4 t 7 comprises a blade 20, a handle portion 2lfand another handle portion 22. The main handle portion 2| may have the form of a ribbed cylinder provided with a recessed part 23 and carrying one end of the blade 20 which is firmly embedded therein.

As shown in Figure 5, the upper end of the handle portion 2| contains an annular recess 24 which encloses a-central support 25 and which is enclosed by walls 26. The support 25 and the wall 26 are integral with the handle portion 2| and may be made of wood, Lucite or some other suitable material. The support 25 has a central curved supporting surface 21, carrying a ball 23.

The ball 28 constitutes a bearing separating the handle portion 22 from the handle portion 2 I.

As shown in Figures 5 and 6, the handle portion 22 has the form of a cup-shaped body which fits into the recess 24 and encloses the support 25. The body 22 has a curved or rounded portion 38 which extends outside of the walls 26 and serves as a rest for the fingers or the hand of the user. The body 22 also has cylindrical walls 30 and 3| separated by an annular groove 29. A ring 31 is mounted upon the support 25 and serves as a race for the body 22 which is somewhat spaced from the walls 26. Due to this arrangement, friction is reduced to a considerable extent.

The walls 26 are provided with a threaded opening 32, containing a screw 33. The inner end of the screw 33, projects into the recess 24 and is situated within the groove 29 of the rotary handle portion 22. To facilitate engagement with the screw 33, the underlying surface 34 of the groove 29 may extend at right angles of the longitudinal axis, while the opposite surface 35 may be oblique or inclined in relation to this axis.

The screw 33 prevents the handle portion 22 from falling out while the ball bearing 28 facilitates the rotary motion between the handle parts 2| and 22.

What is claimed is: A screw driver head, comprising a substantially cylindrical head portion having a screw driving blade connected therewith, and the free end of said head portion having an annular recess formed therein, providing an outer annular wall and an integral central cylindrical support, a second cylindrical head portion of smaller diameter than the first head portion having a central recess formed therein to accommodate rotatable relation to the first head portion, a

ball carried by said support and engaging the bottom in the recess of said second head portion,

and a ring surrounding said support and providing a race for said second head portion;

GUSTAV PRALL. 

